Rock drill



E. G. GARTIN ROCK DRILL May 5, 1936.

Filed March 6, 1934 Patented May 5, 1936 UNITED STATES PATENT OFFICEROCK DRILL Elmer G. Gartin, Claremont, N. H., assignor to SullivanMachinery Company, a corporation of Massachusetts Application March 6,1934, Serial No. 714,316

16 Claims.

This invention relates to rock drills, and more particularly toimprovements in the feeding mechanism of a rock drill of the mounteddrifter type.

An object of this invention is to provide an improved rock drill feedingmechanism. Another object is to provide an improved pneumatic feedingmechanism for a rock drill of the mounted drifter type. A further objectis to provide an improved drill mounting structure for such a drill andimproved means for controlling the flow of pressure fluid to the drill.These and other objects will, however, hereinafter more fully appear.

In the accompanying drawing there is shown for purposes of illustrationone form which the invention may assume in practice.

In this drawing,

Fig. 1 is a side elevational view, with parts in longitudinal section,of the illustrative embodiment of the improved rock drill.

Fig. 2 is a cross sectional View taken substantially on line 22 of Fig.1.

Fig. 3 is an enlarged cross sectional View taken substantially on line3-3 of Fig. 1.

Fig. 4 is a sectional view taken in the plane of line 4-4 of Fig. 3showing the different positions of the controlling valve.

Fig. 5 is a sectional view taken on line 5-5 of Fig. 3, showing severalvalve positions.

- Fig. 6 is a sectional view taken in the plane of line 6-6 of Fig. 3,showing several valve positions.

In this illustrative construction there is shown 35 a rock drill of themounted drifter type generally comprising a guide shell I, a pneumaticfeeding mechanism 2 and a hammer motor 3.

The guide shell I comprises an elongated structural steel element 4 ofT-shaped cross- 40 section, and secured to the depending flange of the Tis a swivel plate 5 having a longitudinal slot 6 for receiving theflange and rigidly secured to the flange by transverse bolts I. Arrangeddirectly above the guide shell in parallelism therewith is areciprocable feed cylinder 8 having a bore 9 for receiving a relativelystationary feed piston I0, and this cylinder has front and rear heads IIand I2. These feed cylinder heads II and I2 are provided with lateralguideways I3, I3 engaging the lateral edges of the top plane surface ofthe structural steel element 4 of the guide shell. The element I2 formsthe rear head block for the cylinder I4 of the hammer motor 3, while thefront head I I is provided with a socket I 5 for receiving the forwardportion of the chuck housing I6 of the hammer motor, this element IIhaving an opening I! through which a drill steel I8 mounted within thechuck housing I6 extends in the manner shown in Fig. 1. The hammer motor3 comprises a usual fluid actuated hammer piston for delivering impactblows to the shank of the drill steel I8, and as the structure of thishammer motor is well known and of a standard design, further descriptionthereof is considered unnecessary.

The hammer motor 3 and the feed cylinder 8 secured to the front and rearheads I I, I2 slide as a unit longitudinally along the guides of theguide shell during feeding of the drill steel during the drillingoperation, while the feed piston I6 is maintained stationary withrespect to the guide shell; and the means for holding the feed piston insuch stationary position comprises an elongated shell brace rod 20extending centrally through a central bore 2i formed in the feed pistonand threadedly secured at its ends within pedestals or brackets 22, 22secured to the opposite extremities of the guide shell, this rod beingrigidly held in position by nuts 23, 23. Interposed between thepedestals 22, 22 and the opposite faces of the feed piston I0 andsurrounding the rod 20 are spacing sleeves 24 and 25, these spacingsleeves engaging the pedestals and feed piston rigidly to hold thelatter against movement in an axial direction longitudinally of theshell. These spacing sleeves which might be termed oppositely extendingstationary piston rods, extend through stufling boxes 26, 26 carriedwithin the front and rear heads II and I2; and these stufling boxes havepackings snugly embracing the outer peripheries of the spacing sleevesto prevent leakage of pressure fluid from the ends of the feed cylinder.

Now referring to the improved valve means for controlling the flow ofpressure fluid to the drill, it will be noted that arranged within atransverse bore 36 formed in the rear head block I2 is a conical-shapevalve 3! having a manual operating lever 32. Secured at 33 to the headblock is a pipe connection 34 for supplying pressure fluid from anysuitable source to the interior of the valve 3| which is herein madehollow at 35. As shown in Fig. 3, leading from the valve bore 30 to thefront and rear ends of the feed cylinder are fluid supply passages 36and 31, the passage 31 being formed in the head block, and as shown inFig. 1, communicating directly with the rear end of the feed cylinderwhile the passage 36 is formed in the head block and the wall of thefeed cylinder and communicates with the forward end of the latter, as isalso shown in Fig. 1. Also formed in the rear head block [2 is a passage38 leading to the supply chamber of the hammer motor 3. Pressure fluidmay be supplied to this passage from the valve 3| through a passage 39formed in the wall of the valve. For supplying pressure fluid from theinterior of the valve to the forward feed passage 36 there is formed onthe exterior periphery of the valve a circumferentially extending groove40 connected to the interior of the valve by a port 4| formed in thevalve wall and communicable with the passage 36. For connecting theforward feed passage 36 to exhaust there is formed on the exterior ofthe valve in the same transverse plane as the groove 40, acircumferentially extending groove 42 communicable with a vent port 43formed in the head block. For supplying pressure fluid from the interiorof the valve to the reverse feed passage 3'! there is formed on theexterior periphery of the valve a circumferentially extending groove 44connected to the interior of the valve by a port 45 formed in the valvewall, and this groove is communicable with the passage 31. For ventingthe reverse feed passage 31 to atmosphere there is formed on theexterior periphery of the valve in the same transverse plane as thegroove 44, a circumferentially extending groove 46 communicable with avent port 41 formed in the head block.

When the valve is in the position a shown in Figs. 4, 5 and 6, pressurefluid flows through the supply connection 34 and the interior of thevalve through port 4| and groove 40 to the forward feed passage 36, thepressure fluid flowing through the passage 36 to the forward end of thefeed cylinder in advance of the feed piston, thereby causing thedrilling motor to be fed forwardly longitudinally along the guide shell.As the drill is fed forwardly when the valve is in this position,pressure fluid is at the same time supplied from the interior of thevalve through port 39 to the motor supply passage 38, thereby causingfull speed actuation of the hammer piston. During forward feeding of thehammer motor, the reverse feed passage 3! is connected to exhaustthrough the groove 46 and vent port 41. When the valve 3| is rotatedinto the position shown at b in Figs. 4, 5 and 6, the flow of pressurefluid from the interior of the valve to the feed passages 36 and 31 iscut off, while the port 39 for supplying pressure fluid to the motorpassage 38 is full on, and as a result the drill steel is ac tuated bythe hammer motor while the latter remains stationary with respect tolongitudinal feeding movement along the guide shell. When the throttlevalve is turned into the position 0 shown in Figs. 4, 5 and 6, pressurefluid is supplied from the interior of the valve through the port 45 andgroove 44 to the reverse feed passage 3l, while the forward feed passage36 is connected to exhaust through the groove 42 and vent port 43, andas a result, the hammer motor is fed rearwardly along the guide shell.At this time the hammer motor is relatively slowly actuated by partialcommunication of the port 39 with the motor supply passage 38. When thethrottle valve is rotated in the position (2 shown in Figs. 4, 5 and 6the supply of pressure fluid to the feed passages 36 and 31 and themotor supply passage 38 is entirely cut ofi, the valve at that timebeing in its neutral or closed position with the entire drill shut down.

As a result of this invention, it will be noted that an improved feedingmechanism is provided for a rock drill of the drifter type havingimproved controlling means whereby the drill is fed and controlled in animproved manner. It will further be noted that by mounting thestationary feed piston in the manner disclosed on the guide shell, animproved reversible pneumatic feed is provided which is of an extremelyrugged design and wherein leakage of pressure fluid from the feedcylinder is reduced to a minimum. Further, by arranging the feedingparts in the manner disclosed, the fluid supply means for the feedcylinder is substantially simplified. These and other uses andadvantages of the improved rock drill will be clearly apparent to thoseskilled in the art.

While there is in this application specifically described one form whichthe invention may assume in practice, it will be understood that thisform of the same is shown for purposes of illustration and that theinvention may be modified and embodied in various other forms withoutdeparting from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a rock drill, a guide shell, a drilling motor mounted thereon, andmeans for feeding the drilling motor along the guide shell including ashell brace rod secured at its ends to the opposite extremities of theguide shell, a feed piston mounted on said brace rod and held againstaxial movement relative thereto, a feed cylinder containing said pistonand slidably guided on said guide shell, said feed cylinder havingportions adjacent each end thereof guidingly engaged by said shell inall positions along the latter, and means for attaching the drillingmotor to the feed cylinder.

2. In a rock drill, an elongated guide shell having upstanding supportsat its opposite extremities, a shell brace rod extending longitudinallyof the guide shell and secured at its ends to said supports, a feedpiston mounted on said brace rod, spacing sleeves interposed betweensaid piston and said supports and surrounding said rod and holding saidpiston against axial movement in longitudinal direction relative to saidrod, a feed cylinder containing said piston and guided on said shell andhaving heads slidingly cooperating with said sleeves, and means forattaching a drill steel hammer motor to said cylinder.

3. In a rock drill, an elongated guide shell, a feed cylinder havingfront and rear heads, said heads having guideways slidably engaging thesides of the guide shell, said cylinder being supported on the guideshell solely by said heads, a stationary feed piston contained in saidcylinder and secured against movement in a longitudinal directionrelative to the shell, and means for attaching a drill steel hammermotor to said cylinder heads independently of said cylinder.

4. In a rock drill, an elongated guide shell formed of a structuralsteel element of T-shaped cross section, a supporting swivel secured tothe depending flange of the T of said guide shell element, a feedcylinder extending longitudinally of said shell and guided forlongitudinal movement therealong, said cylinder having front and rearheads having guideways receiving the lateral edges of the plane topflange of the T of the guide shell element for slidably supporting thefeed cylinder out of direct contact with said shell, and a drill steelhammer motor carried by said feed cylinder heads independently of saidfeed cylinder.

5. In a rock drill. an elongated guide shell, a

stationary feed piston having oppositely extending piston rod meanssecured at its ends to the opposite extremities of the guide shell andforming shell bracing means, a feed cylinder having front and rearheads, said heads having stufling boxes through which said feed pistonrod means extend, said feed cylinder being guided for longitudinalmovement along said guide shell, and a drill steel hammer motor mountedfor movement longitudinally with said feed cylinder and having itsextreme opposite ends connected to said feed cylinder heads.

6. In a rock drill, an elongated guide shell, a stationary feed pistonhaving oppositely extending piston rod means secured at its oppositeends to the opposite extremities of the guide shell and forming shellbracing means, a feed cylinder having front and rear heads guided onsaid guide shell, said heads carrying stufiing boxes through which saidpiston rod means extend, and a drill steel hammer motor mounted on saidfeed cylinder for longitudinal movement therewith relative to the guideshell.

'7. In a rock drill, a guide shell, a pneumatic feed cylinder guided forlongitudinal movement along said shell, a feed piston contained in saidcylinder and held against axial movement with respect to said shell,said feed piston having equal opposed pressure areas, a pressure fluidactuated hammer motor mounted on and movable with said cylinder, andmeans carried by said hammer motor for controlling the flow of motivefluid to said hammer motor and said feed cylinder.

8. In a rock drill, an elongated guide shell formed of a structuralsteel element of T-shaped cross section, a supporting swivel secured tothe depending flange of the T of said guide shell element to provide foradjustment about an axis perpendicular to the plane of the top of saidT, and a drilling motor guided on said shell element and having guidingmeans receiving the lateral edges of the plane top flange of the T ofsaid guide shell element.

9. In a rock drill, an elongated guide shell formed of a structuralsteel element of T-shaped cross section, a supporting swivel secured tothe depending flange of the T of said guide shell element, a drillingmotor guided on said shell element and having guiding means receivingthe lateral edges of the plane top flange of the T of said guide shellelement, and means extending between the ends of said guide shellelement and arranged parallel with the top plane surface thereof andspaced above the latter for bracing said guide shell element.

10. In a rock drill, an elongated guide shell formed of a structuralsteel element of T-shaped cross section, a supporting swivel secured tothe depending flange of the T of said guide shell element, a drillingmotor guided on said shell element and having guiding means receivingthe lateral edges of the plane top flange of the T of said guide shellelement, means extending between the ends of said guide shell elementand arranged parallel with and above the top plane surface thereof forbracing said guide shell element, and means for feeding said drillingmotor with respect to said shell element comprising a feed cylindermovable longitudinally of said shell element and a stationary feedpiston contained in said cylinder and secured to said shell bracingmeans.

11. In a rock drill, an elongated shell element having parallelguideways, separate means extending between the ends of and arrangedparallel with but spaced from the shell guideways for bracing said shellelement, a drilling motor guided on the shell guideways, and means forfeeding said motor longitudinally with respect to said shell guidewaysincluding a feed cylinder movable longitudinally of said shell element,and a stationary feed piston contained in said feed cylinder and securedto said shell bracing means.

12. In a rock drill, an elongated guide shell element having parallelguideways, structurally distinct means extending between the ends of andarranged parallel with but spaced from the shell guideways for bracingsaid shell element, a drilling motor guided on the shell guideways, andmeans for feeding said motor longitudinally with respect to the shellguideways including a feed cylinder movable longitudinally of saidshell, a stationary feed piston contained in said cylinder and mountedon said shell bracing means, feed piston positioning and piston rodforming means comprising sleeves mounted on said bracing means, andpacked heads on said feed cylinder through which the piston rod sleevesextend.

13. In a rock drill, an elongated guide shell element having parallelguideways, a rod extending between the ends of and arranged parallel iththe shell guideways for bracing said shell element, a drilling motorguided on the shell guideways and by said rod, and means for feedingsaid motor longitudinally with respect to the shell guideways includinga feed cylinder movable longitudinally of said shell, a stationary feedpiston contained in said cylinder and mounted on said shell bracing rod,feed piston positioning and piston rod forming means comprising sleevesmounted on said bracing rod, and packed heads on said feed cylinderthrough which the piston rod sleeves extend.

14. In a rock drilling apparatus, an elongated guide shell, a feedcylinder supported on and guided by said guide shell, said feed cylinderhaving heads, and means for attaching a hammer drill motor to saidcylinder heads independently of the cylinder.

15. In a rock drilling apparatus, an elongated guide shell, a feedcylinder having heads by which it is supported and guided on said guideshell, and a hammer drill supported by the heads of said feed cylinderindependently of the cylinder itself.

16. In a rock drill, a guide shell having a brace rod extending parallelto said shell and secured at its opposite ends to the oppositeextremities of the guide shell, a feed piston mounted on said rodsubstantially midway of the length thereof, a feed cylinder surroundingsaid piston and having heads having portions slidably cooperating withsaid guide shell, and a drilling motor carried by said feed cylinder andhaving its rear head formed integral with one head of said cylinder, andsaid motor having a chuck housing at its other end, and said other feedcylinder head having a recess receiving the chuck housing of said drill.

ELMER G. GARTIN.

